The invention relates to a clutch disc, especially for motor vehicles, wherein at least two subassemblies, of which one cannot rotate with respect to a hub and the other cannot rotate with respect to friction linings, can perform a limited amount of angular movement with respect to each other and wherein such angular movement is influenced, at least during certain stages thereof, by energy accumulators and friction. An element which participates in the generation of friction is a washer-like part which is under the action of an axial spring force and is pushed, on the one hand, against a part of the one subassembly and, on the other hand, is form-fittingly secured to one of the parts of the other subassembly.
Such clutch discs have become known, for instance, through German Utility Model No. 7 817 912. There, the following parts are arranged about the hub body, as considered in the axial direction and in the order listed:
an annular washer-like part which is held against movement relative to the hub body in the axial as well as in the circumferential direction, PA1 a cup spring, PA1 a further annular washer-like part which cannot move in the circumferential direction but is displaceable in the axial direction, PA1 a friction or slide lining, PA1 a lining support disc with the friction linings, PA1 a further friction or slide lining, PA1 the hub flange, PA1 the counter disc. PA1 the lining support of the counter-disc, PA1 the washer-like spring element, PA1 the further washer-like part, PA1 a friction or slide lining, PA1 the hub flange, and PA1 the counter- or the lining support disc, PA1 a ring member which is firmly connected to the hub body, for instance, pressed in or on, PA1 the washer-like spring element, PA1 the further washer-like part, PA1 a friction or slide lining, PA1 the drive or the counter disc, PA1 optionally a further friction or slide lining, PA1 the hub flange, and PA1 the counter or drive disc,
The friction can be controlled by the cup spring which bears on the one side against the one and on the other side against the further washer-like part. The further washer-like part is held against rotation with respect to the hub, in that the one washer-like part is formed with arms which extend in the axial direction and into recesses of the further washer-like part. When the friction or slide linings which perform a damping action during relative angular movement wear away, the cup spring can readjust the further washer-like part and the friction or slide linings as well as the lining support disc in the axial direction toward the hub flange.
A certain amount of play is necessary in order to ensure that, during assembly of the clutch disc, the axially extending arms can be inserted into the recesses of the further washer-like part. However, such play increases during operation due to wear upon the arms and surfaces surrounding the recesses, primarily as a result of load changes occurring during operation, especially when idling.
The play between the washer-like parts causes a reduction of friction torque in load-change operation between pulling and pushing. This is noticeable in turn by an annoying, distinctly audible noise.